I'll give it a shot
1. The lesson needs a point.
I do it for me and them, I have a slide at the beginning with 3 things that we are doing. Usually a grammar point, a language point, and a skill.
2. Students talk more than teacher
I'm sure everyone who works in universities has seen how appalling their Chinese classes can be. Just some teacher reading a slide to them while they sleep. They do have books and videos in China they don't need to come to university and sit in a classroom to be given written information. You need to design it so they are doing the work not you. If you get it right the class feels like cheating, you just give them the task and walk around chatting to them.
3. Unpredictability.
There should be a lot of activities, maybe 5 different things a class. Of course you are going to repeat the easy stuff like gap fills and synonym matching, but the meat of the lessons should be different. Like good films, they pretty much all follow a similar structure, but there needs to be different things.
To be honest I've found in China that they are taught English really badly and even the old 1990s games and tricks are new to them, if you go to FluentU they have big lists of all of the classic games.
4.Community.
This is another one that especially in China they seem backwards. Like their education is very didactic. The teacher stands at the front and delivers information, you reproduce this information. This just doesn't work for language teaching, they are world champions at maths and that stuff but they are retarded with foreign languages. You need to make the classroom a safe place where they are not performing they are practicing using the language and realise that it's fine that they are making mistakes, there are no consequences to trying, only to not trying.
5, Energy
The teacher is the leader of the class so you do have to project the energy that you want the class to have. You don't have to be super fun and full of beans, you can be cool and chill, or friendly and nerdy, whoever you are, but you can't be 'i don't want to be here' or you will at best make the students not want to be there and at worst make them hate you.
Especially with youngsters, they see you as an important adult and if you can't live up to that then you just shouldn't be teaching. There are plenty of other better paid and more fun jobs, teachers are important and it's a privilege to do it, but it's also a specific kind of person who does it, there's no shame in just going 'nah I don't like teaching' but if you are at a school ruining a bunch of young people's day, shame on you.